1. Field of the Invention
This invention relates to a process for forming fibers and fibrous webs. In particular, very fine fibers can be made and collected into a fibrous web useful for selective barrier end uses such as filters, battery separators, and breathable medical gowns.
2. Background of the Invention
Rotary sprayers used in conjunction with a shaping fluid and an electrical field are useful in atomizing paint for coating a target device. The centrifugal force supplied by the rotary sprayers produces enough shear to cause the paint to become atomized and the shaping fluid and electrical field draw the atomized paint to the target device. This process has been optimized for the production of atomized droplets. Defects occur when too many atomized droplets agglomerate into larger entities. The prior art teaches toward making atomized droplets and not larger entities.
There is a growing need for very fine fibers and fibrous webs made from very fine fibers. These types of webs are useful for selective barrier end uses. Presently very fine fibers are made from melt spun “islands in the sea” cross section fibers, split films, some meltblown processes, and electrospinning. What is needed is a high throughput process to make very fine fibers and uniform fibrous webs.